With the use of wire ducts in control panel construction, there has been an ongoing problem with wire bundle strain on the wire ducts. More specifically when two sections of wire duct meet and form a 90.degree. union. The wire ducts have sides with a plurality of spaced apart teeth, which hold the wires that enter and exit the wire duct in place. Teeth adjacent the juncture of the wire ducts had to be removed or they became bent when the stiff wire bundles were placed in the wire ducts and bent 90.degree.. U.S. Pat. No. 4,677,734 describes the fabrication of a wire harness or bundle.